ul{
    list-style-type: none;
    margin:0px;
    padding:0px;

}
a:link,a:visited{
    text-decoration: none;
    display: block;
    background-color: blueviolet;
    color:aliceblue;
    width: 50px;
    text-align:center;
}
a:active,a:hover{
    background-color: aqua;
}